1. Field of the Invention
The present invention relates to card connectors. Particularly, the present invention relates to manufacturing card connectors that electrically connect to a miniature memory card such as a micro SD (Secure Digital) card being inserted into the connector.
2. Related Art
A memory card, which is a card-shaped memory device, employs flash memory as a memory medium. The memory card is extremely compact and consumes very little electrical power in reading and writing data. For these reasons, memory cards have become popular as a memory medium for hand-held information devices, as represented, for example, by camera-cellphones and PDAs (Personal Digital Assistant).
In the past, memory cards had the image of having low memory capacity, yet higher costs, compared to other disk-shaped memory devices such as flexible disks (FD) and magnetic optical disks (MO). However, technical advancements made in recent years, and the effects of mass production accompanying popularization of devices that use memory cards, has pushed memory capacity to more than 128 MB, and driven down costs.
Furthermore, a benefit of memory cards is that a drive device is not required to read and write data, unlike FD and MO. For this reason, they are preferred for use in digital cameras, laptop computers and hand-held music players, in which power consumption and portability are important.
Compared to the outside dimensions of a miniSD card at 20 mm (W)×21.5 mm (L)×1.4 mm (T), the outside dimensions of a microSD is 11 mm (W)×15 mm (L)×1.0 mm (T), making it approximately half the width, and an approximately ¼ reduction in volume.
Necessary data are read and written by mounting such memory cards to a card connector. Generally, card connectors are provided with a sliding member that moves along with the memory card being inserted, and a locking mechanism that holds the memory card at the mounted position. In addition, this card connector is configured so that when the mounted memory card is pressed once again, the lock is disengaged and the sliding member ejects the memory card.
From a card connector of this kind of configuration, a card connector has been invented that prevents the memory card from suddenly being ejected when a shock, such as by being dropped, is applied. (For example, Japanese Unexamined Patent Application Publication No. 2003-86289, hereinafter referred to as Patent Document 1.)
Furthermore, from a card connector with this kind of configuration, a card connector has been invented that securely resists the memory card from being forcefully ejected. (For example, Japanese Unexamined Patent Application Publication No. 2005-353368, hereinafter referred to as Patent Document 2.)
FIG. 10 shows a plan view of the card connector of Patent Document 1. This drawing shows a guide member that separates from a heart-shaped cam groove when impacted to prevent disengaging of a locking pin. FIG. 10 of this application is equivalent to FIG. 16 of Patent-Document 1.
As shown in FIG. 10, the card connector 8 is equipped with a housing 81, a sliding member 86, a return spring 83, and a locking mechanism. A card (memory card) 8c is housed in the housing 81. The sliding member 86 is arranged to move in an insertion direction and an ejection direction of the card 8c by engaging the card 8c along with the insertion and ejection of the card 8c. The return spring 83 biases the sliding member 86 in the direction to eject the card 8c. The locking mechanism locks the sliding member 86 at card 8c housed position, resisting the biasing force of the return spring 83.
As shown in FIG. 10, one end of the locking mechanism is provided with a locking pin 84 that pivotably engages the sliding member 86, and a heart-shaped cam groove 8g formed with a cam groove 8h. The locking pin 84 locks the sliding member 86 at the card 8c housed position, and unlocks the sliding member 86 by moving from the locked position to the inside. The heart-shaped cam groove 8g has a locking portion 8i: another end of the locking pin 84 slides.
In addition, in FIG. 10, the housing 81 has a guide member 87 and a biasing spring 85. The guide member 87 moves in the insertion and ejection directions of the card 8c. This guides the movement of the locking pin 84 in cooperation with the heart-shaped cam groove 8g. The biasing spring 85 biases the guide member 87 in a direction to enable the locking pin 84 to lock.
It is disclosed that with the card connector according to Patent Document 1, when there is an impact from outside, the guiding member 87 resists the baising force of the baising spring 85 to prevent another end of the locking pin 84, which is guided by the guide member 87, from detaching from the locking portion 8i, by moving in a direction to separate from the heart-shaped cam groove 8g. More specifically, normally, one end of the locking pin 84 moves to a first oblique surface 8f side formed on one surface of a V-shaped projection that opposes the lock portion 8i to eject the card 8c. In the event that an external impact occurs, the other end of the locking pin 84 moves to a second oblique surface side 8e formed on one surface of the V-shaped projection, and the locking pin 84 is stopped by the heart-shaped cam groove 8g. 
As shown in FIG. 10, the leaf spring 88 applies biasing force for the sliding member 86 to pivot to the card 8c side. A leading end of the sliding member 85 is formed to a substantially L-shape to be a card bearing portion 86b that makes contact with the leading end of the card 8c. Also, an angled convex latching portion 86c is provided between the base portion and the leading end portion of the sliding member 86. The convex latching portion 86c can engage a square latching concave portion 8a formed at a wing of the card 8c. 
As shown in FIG. 10, the card 8c moves in an ejection direction pushed out by the card bearing portion 86b. When the sliding member 86 stops, the convex latching portion 86c abuts the latching concave portion 8a so the card 8c is held in the housing 81. By pulling out the card 8c with a comparatively strong force, the oblique surface of the convex latching portion 86c and the corner of the latching concave portion slide, and the sliding member 86 pivots in the releasing direction to enable the card to be withdrawn.
Here, it is conceivable that with the card connector of Patent Document 1, when the card 8c is ejected, inertial force acts on the card 8c, causing the card 8c to unexpectedly be ejected. To prevent the unexpected ejection of the card 8c, it would be difficult to pull out the card 8c if the oblique surface of the convex latching portion 86c were moderately oblique. It is also difficult to attempt to attain a balance of the oblique surface of the convex latching portion 86c and the biasing force of the leaf spring 88, and to compensate for the manufacturing error of the various elements, including the card, and the clearance. A structure of a card connector that securely prevents unexpected ejection of the card 8c is needed.
FIG. 11 shows a plan view of the card connector according to Patent Document 2, illustrating a card partway ejected from the card connector. FIG. 11 of this application is equivalent to FIG. 2 of Patent Publication 2.
With the card connector 9 shown in FIG. 11, when the card 9c is ejected from the housing 92, the sliding member 94 is released from the lock of the locking pin 96, and is slid from the inside 92a to the entrance 92b by the returning force of a coil spring 95. At that time, the card bearing portion 94b, formed to a substantially L-shape on the leading end of the sliding member 94, pushes the leading end of the card 9c so the card 9c also moves.
In the ejection process of the card 9c, one end 94c of the sliding member 94 starts to compress the rubber brake 97. A hollow portion 97b is provided in the rubber brake 97. This resiliently deforms in a right-angle direction to a compression direction so a contact portion 97a of the triangular shaped leading end compresses a side portion of the card 9c. Therefore, the card connector of Patent Document 2_inhibits the card 9c from unexpectedly being ejected from the housing 92.
Since the card 9c is biased by a rubber body in the card connector disclosed in Patent Document 2, there is a durability problem to wear caused by repeated use. Furthermore, with the card 9c mounted, because the card is held by only the pressing force of a plurality of contacts 93 (see FIG. 11), there is the danger of the card being moved by vibrations, or the like. This can also be a cause of improper contact between the card 9c and the contact 93. A card connector structure that securely maintains the card in its mounted state is needed. The aforementioned problems are issues to be solved by present invention.